One of the most powerful elements of superior genre cinema is that of mystery. It’s hard to process or categorise the unknown. That which cannot be explained by science or which sends your senses into overload. Admittedly, as The Happening so notoriously demonstrated, it doesn’t always guarantee a good film. Especially when the temptation to tie-up loose ends just becomes too much. Thankfully, an atmosphere of intrigue and an air of wrongness never entirely clears from the McManus Brothers’ new film, The Block Island Sound.

Something strange is happening on the coast of Block Island Sound. The fish are dying for no reason and birds are just dropping out of the sky. Angry and frustrated with life, Harry Lynch (Chris Sheffield) keeps a close eye on his father (Neville Archambault), who is having increasingly frequent bouts of wanderings and black-outs. Something is pulling at him. When his sister Audry (Michaela McManus) arrives, a marine biologist tasked with investigating the strange phenomenon, she is concerned by what she finds.

There’s so much going on in The Block Island Sound but all the competing elements intersect to create a strange and sinister fable. Conspiracy theories, ecological disasters, family dramas and existential crises merge into a bold and murky vision. Beautifully filmed against an unnerving backdrop, there are good performances all round and the tension never dissipates. Mixing intrigue and aggrivation, The Block Island Sound is a heady journey into unknown waters.

The Block Island Sound screens at Fantasia Festival.